Is any chance that work on Bug 1413525 will start soon? It would be really great if you could assign engineer to work on this bug.
This single bug (Bug 1413525) (as well as Bug 1378647) are very important for session managers (Session Manager, Tab Mix Plus, Tab Session Manager, MySessions, and maybe Session Buddy in the future) and its users (approx. 1 mln).
Also other bugs probably will be not needed if Bug 1413525 (and maybe Bug 1378647) will be solved.

Bug 1413525’s priority/severity is set to P5 enhancement, but this bug is the most important one blocking Bug 1427928 (meta-bug for session managers) which is set to P3 enhancement.
As you can see >350 users has already voted on Bug 1413525 and on four other session manager-related bugs, including Bug 1378647 and Bug 1427928 (meta-bug).